Magnetic spabk-plfg



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L. W. RASMUSSEN.

MAGNETIC SPARK PLUG.

APPLICATION FILED JULY 6, 19'19.

1 ,355 ,358. Patented Oct. 12, 1920.

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MAGNETIC SPARK PLUG.

APPLICATION FILED Iu1YIe.I9I9.

PI-,ented oct. 12, 1920.

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MAGNETIC SPARK-PLUG.

Specification of Letters Patent.

Application led rluly 16j` 1919. Serial No. 311,227.

T 0 1f/ZZ 'zo fiom it may concern:

Be it known that I, Louis IN. RasMUssEN, a citizen of the 7UnitedStates, resi-ding at Chicago, in the county of Cook and cState ofillinois, have invented certain new and useful Improvements in'h/lagnetic Spark- Plugs; and I do hereby declare the followto be afull, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

The present invention relates to ignition devices Jfor use in internalcombustion engines, and the like, and the primary object of theinvention is to provide a novel and improved make and break spark plug,by means of which the sparks are produced by the making and breakingoi"- the electrical circuit at the electrodes.

Another object of the invention is the provision oi a magnetic sparkplug of novel land improved construction and operation employing anelectro-magnet for vibrating one electrode to rapidly make and break thecircuit when the electrical current is delivered through the plug,thereby assuring of perfect ignition of the charge, and enabling theplug to be used with currents of lower potential than with plugs using aspark gap requiring a current of high potential.

A still further object of the invention is the provision of such a plugembodying a unique assemblage and association of the component elements,providing a thoroughly practical and efficient ignition device forreplacing the ordinary spark gap plug.

l'V ith the foregoing and other objects in view, which will be apparentas the description proceeds, the invention resides in the constructionand arrangement of parts hereinafter described and claimed, it beingunderstood that changes can be made within the scope of what is claimed,without departing Jfrom the spirit of the invention.

The invention is illustrated in the accompanying drawings, whereinFigure 1 is a side elevation of the plug showing the hood and otherportions in section.

Fig. 2 is a plan view with the hood removed.

Fig. 3 is a diametrical section looking in the same direction as in Fi1, portions being shown in elevation.

Fig. 4 is an inner or bottom end view of the plug..

The plug proper is indicated at 1, being threaded to screw into theengine cylinder similar to an ordinary plug, and being provided thereonwith a base 2 on whichthe magnet and corresponding parts are mounted,said base having a marginal rabbet 3 receiving the lower edge or openend of a bell shaped hood 4l which incloses the working parts to protectand conceal same. rlhis hood is removably secured to the base by meansol screws 4: or the like ,'and the base has Lshaped holes 5 opening atone end at the top of base near the margin and at the other end in themargin of the base below the rabbet 5, to provide means for thevengement of a wrench for applying and removing the plug 1, and to alsoafford means oi ventilation ior the circulation of air into and out ofthe hood.

The sparking means of the plug includes a rock shait 6 extendinglongitudinally through the plug 1 and base 2 at one side of the plug,and having secured on its inner end a collar 7 provided with an arm 8 towhich is secured a suitable electrode or contact 9 of such material asto prevent corrosion or disintegration due to they passage ofelectricalcurrent. This electrode or contact 9 cooperates with a similarelectrode or contact 10 secured to the inwardly extending ear 11 at theinner end of a longitudinal rod or bolt 12 extending through alongitudinal bore 13 with which the' plug 1 and base are provided. Therod or bolt 12 has a tapered enlargement 14 at its inner end iittingwithin an insulator 15 seated in the inner en larged end of the bore,13, and the outer end of the bolt or rod extends through an insulator orinsulating washer 16 seated within a recess 17 provided in the base 2, anut 1S being threaded on the outer end of the bolt to draw said boltoutwardly so as to securely fasten it to the plug with the taperedportion 111- iitting tightly in the insulator 15 and the nut 18 withinthe recess 17 below the surface of the base` The electrodes or contacts9 and 10 are adapted to contact, as seen in Fig. 4l, for the passage ofcurrent between the rods 6 and 12. l

Above the base 2 is disposed yan electromagnet 19 extending over therecess 17 and disposed between and carried by lat posts or end pieces 21rising from the base and provided with feet 22 secured on'the base bymeans of screws 23 or the like, providing n a nonrmagnetic support forthe coil or wind- Patented Oct. 12, 1920. Y

ing. One terminal 20 of the electromagnet is clamped under the nut 18 toconnect the magnet in circuit with the sparking device, and the otherterminal 24 of the magnet is secured by means of screw 25 or the like ona contact tongue 26 sefiured on a bridge 2.7 of insulating material thatis in turn mounted on the end pieces 2l ot the magnet, The magnet isthus in circuit with the electrode rod 12 which is insulated from theplug and base, and connection is made through the electrodes or contactswith the rock shaft or rod 6 which is grounded to the plug.

The hood or bell 4 carries the connection for the electrical conductoror wire. Thus, a socket 38 depends on the top oit the hood and isprovided with a threaded stem 29 extending upwardly through insulation30 provided in the top of the hood, and mits 3l are threaded on saidstem to provide a binding post for the connection or the conductor orwire, as well as supporting the socket 28 from the top of the hood. Acontact 32 is slidable in said socket and is yieldimgl,7 depressed by anexpansion spring 33 disposed in the socket behind said contact. T iisContact 32 bears on the contact tongue 26 when the hood 4 is secured onthe base, thus electr'- cally connecting the binding post and conductorwith the electromagnet to complete the circuit, and when the hood-isremoved,

vthe circuit is broken, the contact 82 being removed from the tongue 26.

In order to make and break the circuit when electrical current is passedthrough the plug, an oscillating armature 84 is provided above the baseat one end of the electromagnet, being mounted Jfor swinging movement onthe base by means of a screw 35 serving as a pivot for the armature. Aleaf spring 36 passes loosely around the pivot ot the armature, and hasone end secured to the armature, as at 8'?, while the other end issecured within a post 38 rising from the base. This spring tends to movetrie armature from the core of the magnet. The armature 84 has a wiperarm 39 cooperating with a similar arm 40 secured on the upper end ot therock shaft or rod 6 by means ot a set screw 41 or the like. A coiledwire torsional spring 42 surround the rod between the arm 40 and baseand serves to raise the shaft 6 to bring the collar 7 against the lowerend of the plug, and the upper terminal of the spring engages the arm 40while the lower terminal 43 is adjustably engaged in an arcuate seriesof recesses 44 in the base. This enables the torsion oi the spring 42 tobe adjusted and said spring in tending to unwind will hold the contactor electrode 9 against the contact or electrode 10. ln the absence oelectrical current passing through the magnet, the armature 34 is movedaway from the magnet by spring 36, 1-vithdrawing the arm 39 from the arm40, so that the spring 42 moves the contact 9 against the Contact l0, asseen in Fig'. 4.

ln operation, when electrical current is passed through the plug, it notonly flows through a closed circuit between the contacts 9 and 10, butalso traverses the magnet ,which in being energized, will attract thearmature 34, so that the arm 39 being swung will swing the arm 40,thereby swinging the arm 8 to remove the contact 9 from the contact l0.Consequently, this breaks the circuit and causes a spark to be producedbetween the separated contacts or electrodes 9 and 10, and the breakingof the circuits deenero'izes the magnet, so that the springs 86 and 42will turn the armature and Contact 9, thereby again closing the circuit.This making and breaking oit the circuit is repeated rapidly so that aseries of sparks can be produced by the momentary flow of'currentthrough the plug to assure or" perfect combustion. The flow oi" currentis controlled by the usual timer or distrihuter, and consequently thepresent device can readily replace `the ordinary spark plug withoutturther alterations in the ignition system.

An adjustable stop screw 45 is carried by a post 46 rising 'from thebase, to limit the movement of the armature 34, and thus limit theseparation of the contact 9 trom the contact 10. Tn this way, theseparation of the contacts or electrodes is limited, and this enablestheir separation to be limited to a distance so as to produce a sparkgap across which the sparks can continue to jump after the magnet hasseparated the contacts and as long as current iiows.

V7 hen the hood 4 is removed it is an easy matter to `remove theelectromagnet 19v without disconnecting wires therefrom Having thusdescribed the invention, what is claimed as new is l. An ignition deviceincluding a plug having a base, a rocking rod extending through saidplug, make and break sparking means at the inner end of the plug andoperated by said rod, an electromagnet rigidly secured on said base andhaving one terminal connected to said make and break sparking means,said magnet having a contact for the other terminal, an armature underthe influence of the magnet for operating said rod, a hood removablysecured on the base to inclose the electromagnet. and a binding postcarried by the hood hava contact to bear on the aforesaid contact.

2, An ignition device including .afplug having a base, a pair of rodsextending through the plug, one rod being mounted for rocking movement,the other rod being insulated Jfrom the plug, contacts carried by theinner ends or" said rods, an electromag' net rigidly mounted on the baseand having one terminal connected to the insulated rod, an armatureunder the iniluence of the electro-magnet for operating the rocking rod,a hood removably mounted on the base to inclose said electromagnet, anda binding post carried by the hood, said binding post and electromagnethaving contacts between the hood and base to engage one another when thehood and base are assembled.

3. An ignition device including a plug having a base, an electromagnetsecured on the base parallel therewith, make and break sparking means atthe inner end of the plug, a rocking rod mounted in the plug 'foroperating said sparking means and arranged at one side of saidelectromagnet, an armature pivotally mounted on the base at one end ofthe electro-magnet under the influence thereof, and an operativeconnection between said armature and rod.

An ignition device including a plug having a base, a rocking rod mountedin the plug, make and break sparking means at the inner end of the plugoperated by said rod, an electromagnet above the base, supporting meansextending from the base and carrying said electromagnet, an armaturemounted on the base under the influence of the magnet for operating saidrod, a contact carried by said supporting means to which one terminal ofthe electromagnet is connected, a hood removably mounted on the base toinclose'said electromagnet, and a binding post carried by the hoodhaving a contact t0 bear on the aforesaid contact.

5. An ignition device including a plug, a rocking rod mounted therein,make and break sparking means at the inner end of the plug operated bysaid rod, an electro` magnet at the outer side of the plug, an armaturepivotally carried by the plug under the iniiuence of said magnet, wiperarms carried by said armature and rod for operating said rod from thearmature, and spring means for returning said armature and rod.

6. An ignition device including a plug having a base, a hood on thebase, a make and break sparking device at the inner end of the plug, andelectro-magnetic means carried by the base within the hood for operatingsaid device, said base having openings at its periphery extending to thechamber within the hood for the engagement of a wrench and forventilation.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

LOUIS W. RASMUSSEN.

Witnesses:

ROBERT C. BowMAN, PHILIP R. OFTEDAL.

